diff --git a/qde.py b/qde.py
index 43a2416..8791c57 100644
--- a/qde.py
+++ b/qde.py
@@ -451,12 +451,13 @@ def solve_ode_qubo(system_terms, grid, known_points, bits_integer, bits_decimal,
                     job_label = f'Point {known_points.shape[1]}; Eq. {eq_ind}; Attempt {attempt + 1}'
                     sample_set = sampler.sample_qubo(Q, label=job_label, **kwargs)
                     samples_plain = np.array([list(sample.values()) for sample in sample_set])  # 2D, each row - solution (all bits together), sorted by energy
-                    solution_error = sample_set.data_vectors['energy'][0] + energy_shift
+                    trial_bits = samples_plain[0, :]
+                    solution_error = np.dot(np.matmul(trial_bits, Q), trial_bits) + energy_shift
                     log.write(f'{job_label}; Error {solution_error}\n')
 
                     if solution_error < lowest_error:
                         lowest_error = solution_error
-                        solution_bits = samples_plain[0, :]
+                        solution_bits = trial_bits
 
                     if solution_error < max_error:
                         break
diff --git a/test_core.py b/test_core.py
index a92978f..c1b1991 100644
--- a/test_core.py
+++ b/test_core.py
@@ -182,9 +182,9 @@ def get_qubo_solution(problem, N=100, time_max=400, initial_position=1.3, bits_i
 
 
 def main():
-    # grid, sln, errors = get_qubo_solution(problem=21, N=200)
+    # grid, sln, errors = get_qubo_solution(problem=21, N=50, time_max=400, sampler_name='qbsolv', num_repeats=100)
 
-    _, solution, error = get_qubo_solution(problem=21, N=50, time_max=400, sampler_name='dwave', max_attempts=5, max_error=1e-5, num_reads=10000)
+    _, solution, error = get_qubo_solution(problem=21, N=50, time_max=400, sampler_name='dwave', max_attempts=10, max_error=5e-10, num_reads=10000)
     np.savetxt('solution.txt', solution)
     np.savetxt('error.txt', error)